Патент USA US2113163код для вставки
/ APl'il'5, 1938. ‘K. SCHLESINGER 2,113,163 RELAXATION APPARATUS Filed July 16, 19,55 1/ A 5 " / Luv: fkmuemv ' GE/VEPHTOR J W + . A’ k i; ‘ r!’ Q , FA’HME FREQUQ'NCY GeumnroegrF ' J I7nVenIbr; Patented Apr. 5, 1938 2,113,163 UNITED STATES PATENT OFFICE 2,113,163 RELAXATION APPARATUS Kurt Schlesinger, Berlin, Germany Application July 16, 1935, Serial No. 31,712 In Germany July 20,1934 2 Claims. (Cl. 250-36) In my application Ser. No. 668,940, ?led May 2, 1933, Patent No. 2,083,202, granted June 8, For example, 2 in the line portion is 0,01 mi‘. and in the frame portion 2 mf. 1937, there is described an arrangement for gen erating relaxation oscillations consisting of a The present invention sets forth in what man ner under different conditions of this kind the 5 charging condenser, which is periodically charged through a charging resistance by a direct cur rent source and discharged by means of a grid controlled glow discharge tube. In these discharge tubes the grid does not act 10 as a control element but as blocking element. As long as the control grid possesses a corre sponding negative potential a discharge does not take place, however high the potential may be between the anode and the cathode. Immedi 15 ately, however, the discharge—by shifting of the grid potential-—having once commenced, the same—irrespective of any variation in the grid potentiaL-continues as long as a potential exists between the cathode and the anode. 20 In television receiving arrangements there is applied a synchronizing potential to the grid of the discharge tube. The generator then will pro~ duce relaxation oscillation controlled by the transmitter. It has been pointed out in this earlier applica 25 tion that it is advantageous to insert a resistance in the discharge circuit of the glow discharge tube. This resistance has the object of limiting the intensity of the discharge current, more par 30 ticularly shortly after effected ignition. If this resistance is not provided, there occurs a more or less extensive lack of steadiness in'the tele vision image, which is due to the fact that the points of ignition and quenching of the glow tube 35 do not remain sufficiently constant and each discharge is more or less dependent on the course of the preceding discharge. This state of de pendence is explained by the fact that the in ternal resistance of present-day gas ?lled grid 40 controlled glow discharge tubes is comparatively small, and accordingly even at the commence ment of the ignition very considerable amounts of current are taken from the condenser in very short periods, viz., in a manner which is not resistance I may conveniently be dimensioned. It has been found that the time constant 'TZR'C must always be equal in both circuits. In conse quence, according to the invention, there is found in the line circuit a resistance of 500 ohms and in the image-change circuit a resistance of about 10 3 ohms as optimum. The absolute length of this time constant TZR‘C amounts in the stated cases’taken from practice to approximately 5-10—6,sec. The se~ lection of these particular time constants results 15 from a requirement which is closely associated with the length of the synchronization signals and has likewise been described and substan tiated in an earlier application. The duration of the total discharge should be equal to or ~20 greater than the duration of the synchronization signal. This condition ensures that unsteadiness. of the screen owing to the co-operation of the relaxation connection with the control signals is unable to occur. I claim: 1. A relaxation oscillation arrangement con-, sisting of a line frequency generator and a frame frequency generator, each of said generators comprising a gas ?lled glow discharge device 30v having a hot cathode, a grid and an anode, a chargingvcondenser having one of its ‘electrodes connected to said cathode and its other electrode connected through a resistance to said anode, means for charging said condenser, means to 35 bias said grid negatively with respect to said cathode and. means to apply a synchronizing voltage to said grid, the time constant of the system constituted by said resistance and said charging condenser being in the order of 5-10-6 40 see. for each of said generators. ' 2. A relaxation oscillation arrangement con sisting of a line frequency generator and a frame frequency generator, each of said gen erators comprising a glow discharge device hav» 45 ing a hot cathode, a grid and an anode, a charg arrangement of the resistance l, the condenser’ ing condenser having one of its electrodes con being designated 2, whilst 3 is the gas ?lled grid nected to said cathode and its other electrode connected through a resistance to said anode, controlled glow discharge tube of the line fre quency, l’, 2’, and 3’ indicating corresponding means for charging said condenser, means to 50 bias said grid negatively with respect to said elements of the frame frequency generator. cathode and means to apply a synchronizing It has been found that a resistance l of this voltage to said grid, said charging condenser hav kind is necessary not only in the line relaxation ing a value of 0,02 mf. for the line frequency circuit but also in the vertical relaxation circuit, generator and a value of 2 mi. for the frame fre 55. i. e., the so-called frame circuit. The two relaxa 45 capable of exact control. In the drawing there is shown the fundamental quency generator, said resistance having‘a value tion condensers 2 in these two circuits are, how ever, very diiferent, their ratio being the same as the number of lines in the image, i. e., as 1:200. of 500 ohms for the line frequency and a value of 5 ohms for the frame frequency, generator. KURT SCHLESINGER.